president obama casts a vote for comedy at this weekend's white house correspondents' dinner. >> take the sequester. republicans fell in love with this thing, and now they can't stop talking about how much they hate it. it's like we're trapped in a taylor swift album. captioning funded by cbs >>> this is the "cbs morning news" for monday, april 29th, 2013. >>> good morning and thanks for joining us. i'm vinita nair. we begin this morning into the investigation of the boston marathon bombings. investigators are still trying to determine if the suspects acted alone. the chairman of the house intelligence committee, chairman mike rogers, says persons of interest are being sought, meanwhile the mother is coming under close scrutiny. during a wiretapped phone conversation with her older son, she's heard discussing jihad. ines ferre reports. >> reporter: lawmakers are questioning whether the boston bombing suspects may have had training from terrorists. the chairman of the homeland security system says the tsarnaev brothers used weapons similar to pakistan, afghanistan, and india. >> the ex